An elderly patient will be taking a vasodilator for hypertension. Which adverse effect is of most concern for the older adult patient taking this class of drug?

Correct Answer: D

Rationale: The correct answer is D: Hypotension. Vasodilators relax blood vessels, leading to decreased blood pressure. In older adults, the risk of hypotension is higher due to age-related changes in cardiovascular function. This can result in dizziness, falls, and potential cardiovascular complications. Dry mouth (A), restlessness (B), and constipation (C) are not typically associated with vasodilators and are less concerning compared to the risk of hypotension in elderly patients.

Correct Answer: C

Rationale: The correct answer is C: Take the iron tablets with meals if gastrointestinal distress occurs. This is because taking iron supplements with food can help reduce gastrointestinal side effects such as stomach upset and nausea. It also enhances iron absorption. A is incorrect because taking iron tablets with milk or antacids can decrease iron absorption. B is incorrect because crushing iron pills can alter their effectiveness and may cause irritation to the stomach lining. D is incorrect because black tarry stools are a common side effect of iron supplements and do not necessarily indicate an emergency situation.

Correct Answer: D

Rationale: The elimination rate constant (Kelim) is a key parameter that quantifies the rate at which a drug is removed from the body. It is directly related to the drug's half-life (t ½). The correct answer is D because the half-life is the time required for the drug concentration to decrease by half in the body, which is a crucial factor in determining the rate of elimination. Rate of absorption (A) refers to the speed at which a drug enters the bloodstream, not its elimination. Maximal concentration in plasma (B) and highest single dose (C) are not directly related to the elimination rate constant, making them incorrect choices.

Correct Answer: B

Rationale: The correct answer is B: Procaine. Procaine is an ester local anesthetic that is derived from benzoic acid. It is commonly known as Novocain. Lidocaine (A) is an amide local anesthetic. Ropivacaine (C) is also an amide local anesthetic. Cocaine (D) is a natural alkaloid derivative and not an ester of benzoic acid. Therefore, the correct choice is B as it is the only option that matches the criteria provided in the question.

Correct Answer: D

Rationale: The correct answer is D because Bethanechol is a muscarinic agonist, meaning it specifically targets muscarinic receptors, not nicotinic receptors. Nicotinic receptors are primarily found at neuromuscular junctions and act on skeletal muscle. Bethanechol's main action is on smooth muscle, particularly in the gastrointestinal and urinary tracts. It is used to stimulate bladder contractions in cases of urinary retention and to treat abdominal distention. Choice A is incorrect because bethanechol is not resistant to hydrolysis, and choice B is incorrect because it is purely muscarinic in action, not exerting nicotinic effects.